The invention relates generally to welding systems and more particularly to welding systems utilizing an engine coupled to a welding generator in a single unit.
Welding systems generally use an electrical current (e.g., welding current) to perform welding. The electrical current may be provided by an electrical power source (such as a power grid or battery) or an electrical generator coupled to a mechanical power source. Examples of mechanical power sources include engines that output power via a rotating drive shaft. Typically, the drive shaft is coupled to other devices that consume the energy provided by the rotating drive. For instance, welding systems often include internal combustion engines (such as gas or diesel engines) and an alternator or generator configured to convert the mechanical energy generated by the engine into electrical energy (e.g., electrical current). These systems are often referred to as engine-driven welding generators. An advantage of an engine-driven system is the potential portability of the system. For instance, welding systems that employ a generator coupled to an engine are typically configured as standalone units that do not have connections to a supplemental power source, such as a power grid. This may be useful for systems that are traditionally operated at remote worksites. Such standalone units may also include a battery and an electric starter to start the engine.
The engine used in the welding systems is usually connected to the welding generator via the drive shaft. In addition, the engine generally includes a flywheel to provide rotational inertia to the system. The flywheel also helps achieve a smoother power output by absorbing energy during the firing pulse and dispensing energy during the non-firing portions of the engine cycle. Unfortunately, the flywheel is generally heavy (e.g., a large ferrous disk) as compared to the drive shaft, gears, or other rotating components of the engine. As a result, the flywheel adds considerable weight to the welding system, which is undesirable for a portable engine-driven welding generator. In addition, the flywheel consumes valuable space and increases costs associated with welding systems. Despite all of these drawbacks, the engine performance (e.g., inertia and balancing) relies heavily on the mass of the flywheel.